My (free) PDF, Coordinate Spaces and Transformations in InDesign, now has a 5th Chapter that covers the transform() method.

As a whole, this work investigates how coordinates, locations, bounding boxes, rulers, transformation matrices and related features actually work in InDesign and can be handled from the scripting DOM. Altough the subject requires some effort and is probably not for beginners, it can unlock and solve many problems that developers encounter while dealing with positioning, sizing, and transforming geometric objects in an InDesign document. There are even tasks you just cannot perform without the space-and-transform toolbox.

To my knowledge, no equivalent or similar paper has been published on this particular topic—and Adobe's documentation is pretty confusing, if not inaccurate, regarding the way methods work or the arguments they expect (not to mention the hidden infrastructure they involve.) So it took me years to dig into this topic, test ideas and snippets, and still now I'm pretty sure I have missed important points and made mistakes here or there…

Anyway there is no thread in this forum dedicated to this resource (despite scattered mentions) so I think it would be appropriate to grant it a place in the Documents area. In any case, this topic is open to those who would like to discuss technical points, fix errors and/or suggest additions.